Office



No Model.)

F. MOSSBERG. WRENCH.

No. 482,021. Patented Sept. 6, 1892.

WITNESSES INVENTUR ZQM 7- BY 'fiyhtlo 7 ATTORNE FRANK MOSSBERG, OF ATTLEBOROUGH, MASSACHUSETTS, ASSIGNOR TO THE MOSSBERG MAN UFAOTURING COMPANY, OF SAME PLACE.

WRENCH.

SPECIFICATION forming part of Letters Patent N 0. 482,021, dated September 6, 1892. Application filed December 26, 1891. Serial No. 416,168. (No model.)

To all whom it may concern:

Be it known that I, FRANK MOSSBERG, of Attleborough, in the county of Bristol and State of Massachusetts, have invented certain new and useful Improvements in Trenches;

and I do hereby declare that the following is a full, clear, and exact description thereof,

reference being had to the accompanying drawings, and to the letters of reference IO marked thereon, which form a part of this specification.

This invention relates to that class of adjustable wrenches used to turn screw-nuts, and refers more especially to the devices for IS effecting the adjustment of the wrench to different sizes of nuts and to the construction of those parts by which that adjustment is accomplished.

It is fully illustrated in the accompanying 2o drawings.

Figure 1 is a side elevation of the wrench with a portion of the handle broken away to show the construction and arrangement of p the parts inside. Fig. 2 shows a view from the inner side of the wrench-head or outer jaw. Fig. 3 is an edge view of the wrench as represented in Fig. 1. Fig. 4 is a vertical cross-section taken on line was in Fig. 1, with the end of nut in elevation.

This wrench is intended for one of the short pocket or kit Wrenches, which are usually shortened up in length as much as possible by having the movable jaw and handle in as close proximity to each other as may be or by 5 making them in one piece, as in this case.

It consists of the head or outer jaw a, made in the usual monkey-wrench form, and a shank constructed of two parallel bars 72. (Z, firmly inserted in the jaw a in the position usually occupied by the rectangular shank of the monkey-wrench. The other jaw g, usually considered the movable or adjustable one, is preferably made in one piece integral with the handle n, which is shaped in the most suitable form to hold in the hand. This jaw g and handle n are preferably made of steel in one drop-forging, with an opening at 5, extending through it sidewise. This forging is finished on its outer surface and has two parallel holes drilled nearly through itlengthwise from the jaw end, the centers of which holes agree in distance from each other with the centers of the two parallel bars h d and are made of proper size to let these bars slide snugly in them. One of the bars, preferably h, (the one that comes nearest to a nut when the wrench is used,) has a screw-thread made on that end that slides into the handle for about one-half its length, and a round nut t has a hole made through it, with a screwthread in it fitting on the threaded part of the bar 71.. The nut talso has a screw-thread made on its periphery, agreeing in pitch with the threads inside of the nut, and a portion of the other parallel bar d has that side of it toward the bar It cut away to form a concave face 4;, (see Fig. 4,) and a section of screwthread is out in this concave side, agreeing with the thread 011 the outside of the nut 25, that when that nut is screwed onto the threaded part of the bar it the threads on its outside will fully engage in the threads in the concave side of the bar d. As the two parallel bars h d are held in the holes in the handlein which they slide, so that they cannot spread apart, the threads on the outside of the nut and the threads on the concave side of the bar d are held firmly in engagement with each other. By this arrangement the wrench is made to utilize the full breadth covered by the two bars in resisting any strain tending to open the jaws. This resistance is very much the same as though the two bars h cl were made solidly fast in both jaws, for when the Wrench is applied to a nut to turn it the strain tends to open the jaws and draw the bar It out of the handle, which is resisted by the thread in the nut. At the same time the strain tends to push the bar at into the handle, which is resisted by the thread on the outside of the nut t, which balances the strain of the other bar on the inside of the nut in the other direction. This makes a very strong wrench, which from its construction can be made, mainly, of the best stock bar-steel with the least amount of labor, especially in the case of the head-jaw and parallel bars, which constitute that portion of the wrench that has the most of the work to do.

In putting the wrench together the nut tis inserted in the openings in the handle and the parallel bars h (Z inserted in their respective holes in the end of the movable jaw and handle and pushed down until they reach the nut 15, which is then turned to engage with the screw on the bar h, and at the same time run the thread on its periphery into the thread on the concave side of the bar at and the wrench is ready for use. The section of screw-thread made 011 the concave face of the rod cl and on the outside of the nut trnay be made ratchet shape, as shown in the drawings, to obviate the side-thrust of a V- thread.

Having thus described my improvements, I claim as my invention 1. A wrench having a shank consisting of two parallel bars, in combination with an ad- 

